Jump to content
Brian Enos's Forums... Maku mozo!
itento

10mm OAL for best feeding in STI

Recommended Posts

itento   

I'm dusting off my STI lower/ Caspian upper, Scheumann Hybrid race gun. I'm loading 5.6 Titegroup, 180 MG CMJ in Starline brass at 1.245 OAL. Will probably switch to Zero 180 JHP soon. Does anyone have experience with a like setup? Interested particularily in OAL which will give the most reliable feeding.

Share this post


Link to post
Share on other sites

I think it would depend how your GS set up the gun.

Mine seem to run best between 1.165 and 1.235. I think Derek said he sets them up for 1.190" so that's what I normall load, but the thing will run on 1.135" factory stuff and the 1.250 looong stuff.

Share this post


Link to post
Share on other sites
10mmdave   

Well I'll butt in here I guess (why don't I just read <_< )

OAL for 10mm (which your original post statesI believe) is typically 1.24-1.26 with 1.26

being about the longest you can go.

I just loaded some 200 grn 10mms last night and had to go as far as 1.27 OAL since at the other dims I was crimping over the transion between bullet dia and the

start of the trunketed cone, these are for a revolver so OAL is not a biggy.

I have some 220's I have to load at 1.3 to get a proper crimp, guess I should have sent those bullets back but they work in the revo.

IMO....and for what it's worth, make some dummy rounds with the bullet and

case you want to use, cycle them by hand from the mag into the chamber, see how they feel.

Check to see how the work in the mag, if you load 15-20 do they start to

rattle or start to come up slow from the mag when you empty the mag by hand.

Also make sure the bullet is REALLY designed for 10mm cases (read about

my 220's above) I've found some plated bullets were design more for 40 case and

loaded long to get the extra case capacity.

If I rememeber the Titegroup specs you can reach major well before reaching the

the highest recommended powder charge. Oh what the hech, I went and got the

data. below is from the hodgon web site. (I spelled that wrong didn't I)

___________________________________________________________

180 GR. SIE JHC (No idea who's bullet this is)

COL: 1.260"

HS-6 9.4 1127 35,800 PSI

UNIVERSAL 6.4 1122 32,200 PSI

HP-38 5.8 1061 34,900 PSI

TITEGROUP 6.0grns 1141fps 34,300 PSI = 205 power factor

_____________________________________________________________

200 GR. HDY FMJ (we all know who's this is)

COL: 1.260"

HS-6 8.6 1089 35,900 PSI

UNIVERSAL 5.9 1015 36,900 PSI

HP-38 5.6 1011 35,700 PSI

TITEGROUP 5.3grns 1024fps 36,100 PSI = 204.8 power factor

_______________________________________________________________

Have fun with the Hybrid, I've used one for pins for many years so sorry but

all my data is in the 200-210 power factor range right now.

Power pistol is a great powder in the 10 IMO, cooler burning than the TG.

(course I'm thinking pin loads again)

Share this post


Link to post
Share on other sites
shred   

FWIW, STI mags sometimes don't work well with long 10mm loads. The combination of squared-off TC bullets and the rounded corners in front of the mag can cause hang-ups.

Share this post


Link to post
Share on other sites
itento   

Thanks for the advice. Just getting back to this topic due to wife's medical problem.

Since my first post, I have received both my new Limited gun from Brazos and 6 tuned mags from Beven. Bob's formula for 40 loads for the Limited gun call for 1.22 OAL (lipstick loads) for 180 Zeros JHP using Titegroup or N320. These function 100% in the new mags and I'm very happy with them. For the 10mm Open gun, my previous 1.25 OAL loads would not load in the mags realiably past 15 or 17 rds. They tended to want to nose dive and jam occasionally. I did some experimenting and found that 1.35 OAL (loading short) gives reliable feeding in the gun and in the mags so I'll be using that as a start.

I used to load the 10mm with 135 Nosler JHP with a fairly stiff load of Bluedot to get the comp working and make the old Major pf, and have decided that the 135 and a slower powder is the way to go. The 135 Nosler gives a lot more volume than the 180s at the same OAL. I have a pound of 7N37 that I will begin with and work up slowly since I'll be loading a little short. May go with Bluedot ( a little dirty as I remember) or No 7 or No.9. Any other suggestions?? Thanks

Share this post


Link to post
Share on other sites
I did some experimenting and found that 1.35 OAL (loading short) ...

Any other suggestions?? 

Short? Did you mean 1.135 inches?

Share this post


Link to post
Share on other sites
sargenv   

I didn't know you could load fullpower actual 10 mm ammo to something that short. That is getting to 40 S&W max OAL for SAAMI. I just measured a 10 mm casing from a box of stuff I've loaded for my 610 and it was .972". In that gun I generally load to 1.260". ymmv since that's for an N frame S&W Revo and not a semi.

Since he said 10 mm and not 40 S&W, I assumed he meant the full length stuff.

Vince

Share this post


Link to post
Share on other sites
itento   

Sorry guys, what I meant was 1.235 (i.e. .015 shorter than the 1.250 I was loading to previously). With the 135 Nosler loaded to 1.235 the bullet protrudes about .200 into the case. The case has the volume to load as much as 12.5 gr of 7N37 (mouth of case less .200).

There is no VV data for 10mm and 135 Nosler, but there is for 40S&W (1.126 OAL) and the 135. Starting load is 8.3 gr (1322 fps and 178 pf) and max load is 9.1 gr ( 1434 fps and 193 pf).

I will start with the 8.3 gr which may not make Major (my loads will be .009 longer than the 40 S&W load and hence less pressure and fps) and work up from there.

Share this post


Link to post
Share on other sites
itento   

Just got back from the range. 8.6 gr of 7N37 only come out to 158 pf, but what a consistant load ( 1173, 1174, 1175, 1173, 1178, 1175 fps ), all thrown on my Dillon 650.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×